Question 140428: A spinner is made with twelve 30 degree sectors and is numbered 1 to 12. It is spun twice and the results are added. What is the probability that the sum is larger than 16? If the spinner is spun three times, what is the probability that the sum of the three results is 6 or below?
This is a confusing question. Kelly
Answer by scott8148(6628)   (Show Source):
You can put this solution on YOUR website! with 2 spins, there are 144 (12*12) possible pairs __ to get 17 or more, the possibilities are
12 with 5 or more __ 8
11 with 6 or more __ 7
10 with 7 or more __ 6
__ see the pattern? __ so 36 out of 144 or 1/4
with 3 spins __ 12*12*12 or 1728 possible triplets
1,1 with 4 or less __ 4
1,2 with 3 or less __ 3
2,1 with 3 or less __ 3
2,2 with 2 or less __ 2
1,3 with 2 or less __ 2
3,1 with 2 or less __ 2
1,4,1
4,1,1
2,3,1
3,2,1
__ so 20 out of 1728 or 5/432
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